1. Systems Development Life Cycle Information Systems and Management

2. SDLC Overview (NCC) Initial Strategy Feasibility Study Requirements Analysis Systems Analysis Systems Specification Design Development Testing Implementation Production/Maintenance Review

3. 1.The Initial Strategy Obtain an understanding of the problem Investigate the environment of the: Company Project SDLC

4. 2.Feasibility Study Decide whether the problem is worth solving Types of feasibility 1)Operational 2)Technical 3)Economic 4)Schedule 5)Organizational 6)Political 7)Legal/Contractual SDLC

5. Types of Feasibility Operational –User acceptance Technical –Can proposed components provide the required response? Economic –Will benefits exceed costs (not CBA) Schedule –Will the system be available within the required time frame?

6. Types of Feasibility Organizational –Will the resulting system support organizational objectives? Political –Does the project have senior management support? Legal/Contractual –Will the system function within laws and union agreements?

7. 3.Requirement Analysis Provides information about what the system “should“ do Types of requirements Basic Functional User Transaction User Decision Organization-wide SDLC

8. 4.Systems Analysis (“What“) Produces an accurate record of the current system Fast finding techniques Interview Questionnaire Observation Record Review Document Review Sampling SDLC

9. Documentation Tools Entity Relationship Diagrams Data Flow Diagrams Data Dictionaries Flow Charts Decision Trees Decision Tables Structured English 4.Systems Analysis (“What“) SDLC

10. Concepts Human Behaviour Communication Data Analysis Formal technique of entity analysis and normalization 4.Systems Analysis (“What“) SDLC

11. 5.System Specification Statement of what the new system “will“ do Produced so user and system analyst can be sure they understand and agree Characteristics o Top down o Graphic o Easily Maintained o Understandable o Precise o Logical SDLC

12. Design Shows “how“ the system will operate Identify alternatives and choose the best Cost/Benefit Analysis Net Present Value (Best Method) Must also consider intangible benefits Objectives Flexibility Control Performance

13. Design Components Files Procedure & program specifications Screen layout & dialogue design Forms design Input and output procedures Coding systems Security Systems quality assurance

14. Design Logical Design –Description of the functional requirements of the proposed information systems Physical Design –Specification of the components necessary to put the logical design into action

15. Development Construction of the information system Concerned with productivity –LOC/ELOC/Function Points Decide between in-house development versus a package –RFP and evaluation

16. Testing Levels Unit System Special Volume/year-end Verification Alpha test Simulated environment All logic paths Validation Beta Test Live environment Certification Independent opinion of vendor claims External audit of custom development

17. Testing Bugs versus defect free code

18. Implementation The old systems is replaced by the new system Site preparation Education and training File conversion Change-over Direct Parallel Pilot-organization Phased-system

19. Production/Maintenance Ensure the system continues to operate as required Types Emergency Enhancement Environment

20. Review Develop recommendations for improvement Types of Review Project Determine the appropriateness of project activities and team members System Obtain the users experience with the new system Periodic

21. General Comments 1.The SDLC process is interactive Within stages Back to prior stages 2.Go/No Go decisions At the end of each stage & phase Analysis, design, development 3.Organization of Project Steering Committee, Project Team, Project Management

22. General Comments 4.Managing project review and selection Portfolio Analysis Asses the individual projects based upon project complexity and technical maturity of the organization Decide on the mix of high and low risk projects taking into consideration functional requirements

23. Software Development Methodologies Waterfall RAD: Incorporates prototyping Extreme Programming Method: small reusable modules Agile Method: Extreme method & limited project scope Fast continuous delivery Improved customer satisfaction

24. The Changing IS Development Environment The SDLC is affected directly by: Structured Methods Prototype Application Packages End-user Development CASE Changes outside the immediate Domain Outsourcing Knowledge of Information Technology Business Process Re-engineering (BPR)

25. Structured Methods Highly formalized techniques and methods of analysis and documentation Specifications need to be: Comprehensible to the user & accurate and detailed enough for the designer  Database software concentrates on a logical system definition  Structured techniques ERD DFD DD

26. Prototype - The process of building an experimental model of a proposed system quickly and inexpensively for demonstration and evaluation so that users can better determine information requirements.

27. Prototype Purpose o Reduce the time for the user to see something tangible o Allows for rapid feedback from the user to the designer o Allows for meaningful user involvement in systems analysis and design

28. Prototype Comments o Changes should be encouraged o Be aware it is only a model o Doesn’t include the editing and error checking of a finished system o Purpose it to show what CAN BE accomplished and not to demonstrate that a system is complete

29. Prototyping Approaches Type II o A throwaway model o Uses a 4GL language to develop the model o Uses a 3GL language to develop the final system Type I o An iterative model o Uses the prototype as the final system after a series of evolutionary changes based upon user feedback

30. Application Packages A set of prewritten, pre-coded application software programs that are commercially available for sale of lease

31. Selecting Application Packages Request for Proposal Evaluation Criteria Quantitative evaluation technique –The package must meet at least 90% of the requirements to provide you with advantages of use

32. Package Customization Do NOT do it!

33. System Integration Refers to the practice of combining various components that are purchased and/or custom developed to form a complete system  The difficulty arises when system integration involves legacy systems, which may be based on outdated technology

34. Advantages of Packages The system exists and can be tried out Less total development time Should result in lower cost May have more functions or extra features Programs included in the system will have been debugged

35. End-User Development The development of information systems by end users with little or no formal assistance from technical specialists Grew out of frustration too long to process new system or system change requests Software Crisis Y2K Excess demand for IS development Identified backlog: 30 work months Hidden back-log: 4-7 years

36. Advantages Requirements determined by users Increased user involvement and satisfaction Control of the system development process by users Reduced application backlog

37. Information Centre A Unit within the Information System Department which supports End-user development with training and support Provides advice on hardware and software selection, and training Ensures: o Data Availability o End-users control their own data and share it through local networks o Corporate data are downloaded from corporate computers o Data Security o Access is limited to only the data users needs

38. Computer-Aided Systems Engineering (CASE) In the past SDLC has often been considered too: Inflexible Time consuming Expensive And thus creating a backlog in systems development.  CASE involves automating some of the SDLC processes

39. CASE Upper CASE (front end) Lower CASE (back end) Integrated CASE –All SDLC, calendaring and PM Forward Engineering Reverse Engineering (backward engineering) –Y2K  Note: No SDLC stages are eliminated

40. Outsource The practice of contracting computer centre operations, telecommunication networks or applications development to external vendors  This will bring economies of scale into the situation

41. Advantages Economy Service Predictability Flexibility Freeing resources o Human resources for other projects o Finances

42. Disadvantages Loss of control Vulnerability of strategic information Dependency

43. Knowledge of Information Technology People, in general, commonly interact with IT on a daily basis. History Phone o Originally used for emergencies in munitions factories and for changes to train schedules Car o Potentials sales volume was limited to the number of individuals thought capable of driving an automobile Computer o Originally expected only a few computers would be sold – now they are everywhere!

44. Business Process Re-Engineering (BPR) The radical redesign of business processes, combining steps to cut waste and eliminate repetitive, paper- intensive tasks in order to improve costs, quality or service, and to maximize the benefits of information technology.  New ways are being investigated to apply IT to support business goals and gain competitive advantage  Emphasis changing from efficiency to effectiveness “Paving the cow paths” Hammer Davenport